It is well known that soymilk refuse is rich in dietary fiber and is a food resource with high nutritive values. However, since soymilk refuse has difficulties in food handling because of its rapid deterioration with bacterial growth, its use as a foodstuff has been restricted to only a daily delivery food so that a large amount of the soymilk refuse has been treated as industrial waste so far. Therefore, there has been demand for effective utilization of the soymilk refuse.
In some examples of effective utilization of the soymilk refuse, the soymilk refuse, which has previously been subjected to enzymatic reactions such as lipolysis and proteolysis, has been used as a confectionary stuff, for example, for preparing cookies, and as a cooking stuff for preparing croquette or hamburger, and dry soymilk refuse has been utilized in culture media for mushroom cultivation, in beds for preserving vegetables, and as feed in stock farming. Considering its high drying cost, however, its effective utilization with high value added has to be desired.
On the other hand, fermented food of soymilk refuse seems to be hopeful for human health because it contains dietary fiber and chitin-chitosan which is derived from the mold used; the former controlling intestinal functions and lowering blood cholesterol levels, the latter having physiological activities. Among the fermented food of soymilk refuse hitherto prepared, there is one example made by fermentation with a mold, Tempeh. But the food has not come into Japanese market because it does not satisfy Japanese palatability.
Under the above described circumstances, i.e. in which the soymilk refuse has not effectively been used so far regardless of its outstanding characteristic suitable for excellent foodstuff as health food, and in which the conventional products made from the soymilk refuse has not satisfied Japanese palatability, whereby the soymilk refuse has had to be treated as industrial waste, an object of the invention is to provide a method for producing highly nutritive fermented food with excellent palatability from the soymilk refuse, which food will come to be popular in the market as health food.